Method for determining whether or not test sample contains phytopathogenic fungus

Abstract

The present invention provides a method for determining whether or not a test sample contains a phytopathogenic fungus selectively from two kinds of fungi of a phytopathogenic fungus and a non-phytopathogenic fungus. The method according to the present invention comprises: (a) putting the test sample on a front surface of a substrate comprising a through hole; wherein the substrate comprises a cellulose film on the back surface thereof; the cellulose film has a thickness of not less than 0.5 micrometers and not more than 2 micrometers; and the through hole has a cross-sectional area of not less than 7.065 square micrometers and not more than 19.625 square micrometers; (b) leaving the test sample at rest; (c) observing a back surface of the film; and (d) determining that the test sample contains the phytopathogenic fungus, if a fungus is found on the back surface of the film.

The invention claimed is: 
     
       1. A method for determining whether or not a test sample contains a phytopathogenic fungus, wherein the phytopathogenic fungus is selected from the group consisting of  Fusarium oxysporum, Pyricularia grisea , and  Colletotrichum gloeosporioides , the method comprising steps of:
 (a) putting the test sample on a front surface of a substrate comprising a through hole, wherein:
 the substrate comprises a cellulose film on the back surface thereof, 
 the cellulose film has a thickness of not less than 0.5 micrometers and not more than 2 micrometers, and 
 the through hole has a cross-sectional area of not less than 7.065 square micrometers and not more than 19.625 square micrometers; 
 
 (b) leaving the test sample at rest after the step (a); 
 (c) observing a back surface of the film after the step (b); and 
 (d) determining that the test sample contains the phytopathogenic fungus, if a fungus is found on the back surface of the film in the step (c). 
 
     
     
       2. The method according to  claim 1 , further comprising:
 a step of bringing the back surface of the cellulose film into contact with a fluorescent agent having fungus combining ability between the step (b) and the step (c). 
 
     
     
       3. The method according to  claim 1 , further comprising:
 a step of supplying a culture medium to the test sample before the step (b). 
 
     
     
       4. The method according to  claim 3 , wherein
 the culture medium is a liquid culture medium. 
 
     
     
       5. The method according to  claim 3 , wherein
 the test sample is left at rest while the back surface of the cellulose film is in contact with the culture medium in the step (b). 
 
     
     
       6. The method according to  claim 3 , wherein
 the culture medium is a solid culture medium. 
 
     
     
       7. The method according to  claim 1 , wherein
 the test sample is solid. 
 
     
     
       8. The method according to  claim 7 , wherein
 the solid test sample is at least one selected from the group consisting of soil and a crushed plant. 
 
     
     
       9. The method according to  claim 1 , wherein
 the test sample is liquid. 
 
     
     
       10. The method according to  claim 9 , wherein
 the liquid test sample is at least one selected from the group consisting of agricultural water, a liquid used for hydroponic culture, a liquid used for washing a plant, a liquid extracted from a plant, a liquid used for washing an agricultural material, and a liquid used for washing clothing or a shoe. 
 
     
     
       11. The method according to  claim 1 , wherein the test sample is left at rest for 24 hours at step (b). 
     
     
       12. A method for determining whether or not a test sample contains a phytopathogenic fungus, wherein the phytopathogenic fungus is selected from the group consisting of  Fusarium oxysporum, Pyricularia grisea , and  Colletotrichum gloeosporioides , the method comprising the following steps (a) and (b):
 (a) observing a back surface of a cellulose film, wherein
 the cellulose film is adhered on a back surface of a substrate, 
 the substrate comprises a through hole, 
 the test sample is disposed on a front surface of the substrate, 
 the cellulose film has a thickness of not less than 0.5 micrometers and not more than 2 micrometers, and 
 the through hole has a cross-sectional area of not less than 7.065 square micrometers and not more than 19.625 square micrometers; and 
 
 (b) determining that the test sample contains the phytopathogenic fungus, if a fungus is found on the back surface of the film in the step (a).